$ { \left[\begin{array}{rrr}{-2} & {-2} & {1} \\ {2} & {1} & {1}\end{array}\right]-\left[\begin{array}{rrr}{2} & {3} & {4} \\ {0} & {4} & {-2}\end{array}\right] = {?} } $
Answer: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{-2}-{2} & {-2}-{3} & {1}-{4} \\ {2}-{0} & {1}-{4} & {1}-{-2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{-4} & {-5} & {-3} \\ {2} & {-3} & {3}\end{array}\right]}$